The field of application of the invention is that of pieces of equipment of public works machines, in particular buckets, skips or other receptacles which may scrape, pick up and displace materials with view to their discharge from a given location to other operating stations by means of public works machines.
The present invention relates to a mechanical system comprising a support, a wearing part and a device for connection between the wearing part and its support, notably a tooth and its support belonging to a public works machine piece of equipment. The invention also relates to a public works machine bucket comprising at least such a system.
In a known way, a bucket includes a leading blade equipped with wearing parts provided for their capability of penetration of the material and of protection of the other constitutive elements of the bucket. On leading blades are attached adapter-supports having a profiled nose, while the wearing parts are teeth or shields which will be positioned on the adapter-support according to a specific connection. This connection is temporary in order to allow replacement of the wearing parts after wear.
The connection between the wearing part and its support may be achieved by keying. In order to be performing, the keying devices should ensure a rigid connection of the elements which they join up. Conventionally, assembling and disassembling of the keyings is carried out by the action of percussion tools, with the risk of injuries for the operators.
Keying devices are also known which do not require the use of percussion tools. In the past, such devices required pieces of constraining special equipment, notably for disassembling the wearing part. Further, such devices were complex to manufacture and to use.
WO-A-2013/030335 describes a mechanical system comprising an improved keying device, not requiring the use of percussion tools. The device comprises an elastically deformable sheath and a rigid key, mobile and secured to each other in rotation.
US-A-2008/209772 describes a mechanical system, comprising a support 106, a wearing part 102 and a connecting device between the wearing part 102 and its support 106. The connecting device comprises a body 100, a sheath 200, a key 300 and a rod 350. The body 100 is provided with an internal cavity and an adjustable external wall in a housing of the support 106. The sheath 200 is in an elastically deformable material, provided with an internal cavity 202 and with an adjustable external wall 204+206 in a housing of the body 100, and not in a housing of the support 106. The key 300 includes an elongated body 304 along a key axis and a head provided with a latch 340. The rod 350 may be inserted into a housing of the body 100 for blocking the key 300 in position in the body 100.